package vn.isolar.system.audio;


import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import android.media.AudioFormat;
import android.media.AudioRecord;
import android.media.MediaRecorder;
import android.os.Environment;
import android.util.Log;

public class Recorder {
	int RECORDER_SAMPLERATE = 16000;
	int RECORDER_CHANNELS = AudioFormat.CHANNEL_IN_MONO;
	int RECORDER_AUDIO_ENCODING = AudioFormat.ENCODING_PCM_16BIT;
	byte RECORDER_BPP = 16;
	int bufferSizeInBytes = AudioRecord.getMinBufferSize(RECORDER_SAMPLERATE,
			RECORDER_CHANNELS, RECORDER_AUDIO_ENCODING);
	// Initialize Audio Recorder.
	AudioRecord audioRecorder = new AudioRecord(MediaRecorder.AudioSource.MIC,
			RECORDER_SAMPLERATE, RECORDER_CHANNELS, RECORDER_AUDIO_ENCODING,
			bufferSizeInBytes);
	private String fn;
	
	public String startRecord(){
		int numberOfReadBytes = 0;
		byte audioBuffer[] = new byte[bufferSizeInBytes];
		boolean recording = false;
		float tempFloatBuffer[] = new float[3];
		int tempIndex = 0;
		int totalReadBytes = 0;
		byte totalByteBuffer[] = new byte[60 * 44100 * 2];
		audioRecorder.startRecording();
		// While data come from microphone.
		while (true) {
			float totalAbsValue = 0.0f;
			short sample = 0;

			numberOfReadBytes = audioRecorder.read(audioBuffer, 0,
					bufferSizeInBytes);

			// Analyze Sound.
			for (int i = 0; i < bufferSizeInBytes; i += 2) {
				sample = (short) ((audioBuffer[i]) | audioBuffer[i + 1] << 8);
				totalAbsValue += Math.abs(sample) / (numberOfReadBytes / 2);
			}

			// Analyze temp buffer.
			tempFloatBuffer[tempIndex % 3] = totalAbsValue;
			float temp = 0.0f;
			for (int i = 0; i < 3; ++i)
				temp += tempFloatBuffer[i];

			if ((temp >= 0 && temp <= 350) && recording == false) {
				Log.i("TAG", "1");
				tempIndex++;
				continue;
			}

			if (temp > 350 && recording == false) {
				Log.i("TAG", "2");
				recording = true;
			}

			if ((temp >= 0 && temp <= 350) && recording == true) {
				Log.i("TAG", "Save audio to file.");

				// Save audio to file.
				String filepath = Environment.getExternalStorageDirectory()
						.getPath();
				File file = new File(filepath, "AudioRecorder");
				if (!file.exists())
					file.mkdirs();

				fn = file.getAbsolutePath() + "/"
						+ System.currentTimeMillis() + ".wav";
				long totalAudioLen = 0;
				long totalDataLen = totalAudioLen + 36;
				long longSampleRate = RECORDER_SAMPLERATE;
				int channels = 1;
				long byteRate = RECORDER_BPP * RECORDER_SAMPLERATE
						* channels / 8;
				totalAudioLen = totalReadBytes;
				totalDataLen = totalAudioLen + 36;
				byte finalBuffer[] = new byte[totalReadBytes + 44];

				finalBuffer[0] = 'R'; // RIFF/WAVE header
				finalBuffer[1] = 'I';
				finalBuffer[2] = 'F';
				finalBuffer[3] = 'F';
				finalBuffer[4] = (byte) (totalDataLen & 0xff);
				finalBuffer[5] = (byte) ((totalDataLen >> 8) & 0xff);
				finalBuffer[6] = (byte) ((totalDataLen >> 16) & 0xff);
				finalBuffer[7] = (byte) ((totalDataLen >> 24) & 0xff);
				finalBuffer[8] = 'W';
				finalBuffer[9] = 'A';
				finalBuffer[10] = 'V';
				finalBuffer[11] = 'E';
				finalBuffer[12] = 'f'; // 'fmt ' chunk
				finalBuffer[13] = 'm';
				finalBuffer[14] = 't';
				finalBuffer[15] = ' ';
				finalBuffer[16] = 16; // 4 bytes: size of 'fmt ' chunk
				finalBuffer[17] = 0;
				finalBuffer[18] = 0;
				finalBuffer[19] = 0;
				finalBuffer[20] = 1; // format = 1
				finalBuffer[21] = 0;
				finalBuffer[22] = (byte) channels;
				finalBuffer[23] = 0;
				finalBuffer[24] = (byte) (longSampleRate & 0xff);
				finalBuffer[25] = (byte) ((longSampleRate >> 8) & 0xff);
				finalBuffer[26] = (byte) ((longSampleRate >> 16) & 0xff);
				finalBuffer[27] = (byte) ((longSampleRate >> 24) & 0xff);
				finalBuffer[28] = (byte) (byteRate & 0xff);
				finalBuffer[29] = (byte) ((byteRate >> 8) & 0xff);
				finalBuffer[30] = (byte) ((byteRate >> 16) & 0xff);
				finalBuffer[31] = (byte) ((byteRate >> 24) & 0xff);
				finalBuffer[32] = (byte) (2 * 16 / 8); // block align
				finalBuffer[33] = 0;
				finalBuffer[34] = RECORDER_BPP; // bits per sample
				finalBuffer[35] = 0;
				finalBuffer[36] = 'd';
				finalBuffer[37] = 'a';
				finalBuffer[38] = 't';
				finalBuffer[39] = 'a';
				finalBuffer[40] = (byte) (totalAudioLen & 0xff);
				finalBuffer[41] = (byte) ((totalAudioLen >> 8) & 0xff);
				finalBuffer[42] = (byte) ((totalAudioLen >> 16) & 0xff);
				finalBuffer[43] = (byte) ((totalAudioLen >> 24) & 0xff);

				for (int i = 0; i < totalReadBytes; ++i)
					finalBuffer[44 + i] = totalByteBuffer[i];

				FileOutputStream out;
				try {
					out = new FileOutputStream(fn);
					try {
						out.write(finalBuffer);
						out.close();
					} catch (IOException e) {
						// TODO Auto-generated catch block
						e.printStackTrace();
					}

				} catch (FileNotFoundException e1) {
					// TODO Auto-generated catch block
					e1.printStackTrace();
				}

				// */
				tempIndex++;
				break;
			}

			// -> Recording sound here.
			Log.i("TAG", "Recording Sound.");
			for (int i = 0; i < numberOfReadBytes; i++)
				totalByteBuffer[totalReadBytes + i] = audioBuffer[i];
			totalReadBytes += numberOfReadBytes;
			// */

			tempIndex++;
		}
		audioRecorder.stop();
		return fn;
	}
}
